Lourinhã Formation
Late Jurassic geological formation in Portugal
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The Lourinhã Formation (Portuguese pronunciation: [loɾiˈɲɐ̃] ⓘ) is a fossil-rich geological formation in western Portugal, named for the municipality of Lourinhã. The formation is mostly Late Jurassic in age (Kimmeridgian/Tithonian), with the top of the formation extending into the earliest Cretaceous (Berriasian). It is notable for containing a fauna especially similar to that of the Morrison Formation in the United States and to a lesser extent to the Tendaguru Formation in Tanzania. There are also similarities to the nearby Villar del Arzobispo Formation and Alcobaça Formation. Besides the fossil bones, Lourinhã Formation is also well known for the fossil tracks and fossilized dinosaur eggs.[1][2]
- Consolação Sub-Basin - Praia da Amoreira-Porto Novo Member, Praia Azul Member, Santa Rita Member
- Turcifal Sub-Basin - Assenta Member
| Lourinhã Formation | |
|---|---|
| Stratigraphic range: late Kimmeridgian-earliest Berriasian ~ | |
| Type | Geological formation |
| Sub-units |
|
| Underlies | Porto da Calada Formation |
| Overlies | Consolação & Alcobaça Formations |
| Thickness | 200–1,100 metres (660–3,610 ft) |
| Lithology | |
| Primary | Sandstone, mudstone, marl |
| Other | Conglomerate, limestone |
| Location | |
| Coordinates | 39.23°N 9.32°W |
| Region | Lisbon Region |
| Country | Portugal |
| Extent | Lusitanian Basin |
| Type section | |
| Named for | Lourinhã |
| Named by | Hill |
| Year defined | 1988 |
The Lourinhã Formation includes several lithostratigraphic units, such as Praia da Amoreira-Porto Novo Members, Praia Azul Member, the Santa Rita Member, and the Assenta Member.[3] The stratigraphy of the formation is complex and controversial, with the constituent member beds belonging to the formation varying between different authors.[4]
Lithology and depositional history
Depositional history

The Lourinhã Formation is located within the Lusitanian Basin, a mostly onshore North South orientated rift basin within western Portugal, formed during the Opening of the North Atlantic Ocean, with sediment deposition beginning during the Late Triassic-Early Jurassic. It primarily consists of syn-rift near-coastal continental siliciclastic sediments, with several marine intercalations. The primary flow direction was North to South, originating from Galicia and flowing between the Iberian landmass to the east and the now largely submerged Berlengas horst, a north–south oriented ridge, to the west.
The Lourinha Formation is interpreted as being an island, separated by North America and the rest of Europe by marine barriers.[5] The Paleoclimate is interpreted as being semi arid, with less than 50 cm of annual precipitation and an average annual temperature of 16 to 19 °C.[4]
Stratigraphy
The unit was first formally proposed by Hill in 1988.
The stratigraphy of the Lourinhã Formation is complex and varies between sub-basins with several competing stratigraphic proposals and there is currently no consensus on the matter, one of the most recent stratigraphies,[4] divides the formation into three members which are from oldest to youngest the Praia da Amoreira-Porto Novo Member, Praia Azul Member, and the Assenta Member.
Praia da Amoreira-Porto Novo Member
The Praia da Amoreira-Porto Novo Member is composed of the Praia de Amoreira Member, which consists of massive mudrock-sand with metre thick sandstone lenses, with massive mudrock with calcrete. The overlying Porto Novo Mb. consists of massive bodies of sandstone, often cross bedded. The environment of deposition is interpreted as a meandering fluvial system, while the Porto Novo Mb is interpreted as a deltaic deposit. It is interpreted to be latest Kimmeridgian in age, and overlies the Consolacao Unit at the top of the Aulacostephanus eudoxus ammonite zone.[4][6] The Continental facies of the Porto Novo Member intersperse into the Praia Azul Member & they transition vertically and laterally into each other.[7] At Vale Pombas at least 2 tongues of the Porto Novo Member are interspersed with 2 tongues of the Praia Azul Member.[7] At Porto Dinheiro, the continental fluvial environment at the top of Porto Novo Member show tidal influence, evidence of interaction with the coastal ecosystem of the Praia Azul Member.[8] In the region from Paimogo to Areia Branca the overlaying deposits of the Praia Azul Member correspond to the upper Porto Novo Member in that section, implying they intercalate.[4] These details indicate the Praia Azul & Porto Novo Members represent laterally equivalent environments deposited simultaneously in adjacent, shifting, and laterally migrating sedimentary environments.
Praia Azul Member
The Praia Azul Member, formerly known as the Sobral unit/member is 80 to 130 metres thick and consists of tabular marls and mudstones, with rare sandstones bodies. There are three distinct laterally extensive (>20 km) thin shelly carbonate horizons within this member, indicating brief marine transgressions. South of Santa Cruz primarily consists of sandstone with rare conglomerate. The age is considered to be latest Kimmeridgian to earliest Tithonian, correlated to the ammonite zones of Hybonoticeras beckeri and Hybonoticeras hybonotum.[4][6]
Santa Rita Member + Assenta Member
The Santa Rita Member in the Consolação sub-basin and its lateral equivalent in the Turcifal Basin the Assenta Member is around 300 metres thick and predominantly consists of mudstones with frequent layers of caliche. Near the top of the member several layers of tens of metres thick nodular and marly bioclastic limestones are present, containing marine benthic forams, the nodularity is derived from intense Thalassinoides burrowing. It is predominately late Tithonian in age, with the last few metres probably being earliest Berriasian, with the top of the formation roughly correlative with the base of the magnetochron M18n. (~144.7 Ma)[9][4] The environment of deposition is interpreted as being an upper fluvial-dominated delta to meandering fluvial systems flowing on a paralic plain.
Fauna
Dinosaurs
In a 2003 study, an analysis of all Portuguese dinosaurs was published. The study created a cladogram showing the possible relations of all Portuguese dinosaurs, including those at the time known from the Lourinhã Formation.[10]
Ornithischia
Color key
|
Notes Uncertain or tentative taxa are in small text; |
Ornithopods
| Genus | Species | Member | Material | Notes | Images |
|---|---|---|---|---|---|
| Ankylopollexia indet.[11] | Indeterminate |
|
Appendicular, axial, and cranial elements | The remains from Porto Novo pertain to a large ankylopollexian.[12]
The dorsal vertebrae and scapula from Praia Azul are larger than most Ankylopollexia material from Lourinha & similar in size to Camptosaurus sp.[11] |
|
|
Intermediate[13] |
Limb material[13] |
Now referred to its own genus, Draconyx, along with some other material.[13] | |||
|
D. loureiroi[13] |
Praia Azul Member[14] |
A partial skeleton including teeth, caudal vertebrae, a chevron, a partial forelimb, and a partial right hindlimb[14] |
An ankylopollexian | ||
| Dryosauridae indet.[11] | Indeterminate | Praia Azul Member
Praia da Amoreira-Porto Novo Member |
Appendicular, axial, and cranial elements | Various remains of indeterminate dryosaurids. | |
| Eousdryosaurus[15] | E. nanohallucis[15] | Praia Azul Member[16] | A partial postcranial skeleton. | A basal iguanodontian ornithopod. | |
| Hesperonyx[8] | H. martinhotomasorum | Porto Novo Member | Bones from the forelimbs and hindlimbs | A dryomorphan iguanodontian with uncertain affinities | |
|
Ornithopoda indet.[17] |
Intermediate[17] |
Praia Azul Member[18] |
A single track[17] |
Gigantic track indicating an ornithopod with a hip height of 2.5 meters. No known Jurassic Ornithopod reaches this size; the only known evidence for such sizes in this group is at the time. Found alongside the Deltapodus print.[17] | |
|
P. henkelli.[10] |
Two teeth | ||||
Color key
|
Notes Uncertain or tentative taxa are in small text; |
Thyreophorans
| Genus | Species | Member | Material | Notes | Images |
|---|---|---|---|---|---|
|
D. armatus[19] |
A specimen consists of a collection of skeletal remains consisting of a nearly complete dorsal vertebra, three dorsal vertebral centra, nine dorsal neural arch fragments, an incomplete sacrum that preserves only four sacral vertebrae, two sacral ribs, fragments of the dorsal sacral plate, the anterior process of the right pubis, and numerous fragmentary remains belonging to the dermal armor, in addition to several indeterminate fragments. | A stegosaurid, material referred to Miragaia may represent this taxon | |||
|
D. brodricki[21] |
Eleven tracks; Nine pes and two manus prints.[21] |
The tracks can be separated into three different morphologies. However, all fall within the range of the ornithopod association of the pes and manus tracks to the same taxon, cannot be directly supported. Preserve various well-preserved skin impressions. The largest prints are larger than those from the type horizon. The tracks are individually represented and do not form any sort of trackway, though one print is associated with a giant ornithopod track,[17] potentially representing that the creatures were traveling together or were otherwise going to a similar location. Another is similarly associated with theropod and sauropod prints.[21] | |||
| Dracopelta[10] | D. zbyszewskii[10] | Assenta Member | An ankylosaur. | ||
| Miragaia[22] | M. longicollum[22] | Holotype, neck, partial skull, forelimbs, ribs. Tentative juvenile specimen assigned to this taxon.[22] | A stegosaur with an unusually long neck of 17 cervicals, with more neck vertebrae than most sauropods.[22] Probably a junior synonym of Dacentrurus.[24][25] | ||
Color key
|
Notes Uncertain or tentative taxa are in small text; |
Other Ornithischians
Saurischia
Color key
|
Notes Uncertain or tentative taxa are in small text; |
Sauropods
| Genus | Species | Member | Material | Notes | Images |
|---|---|---|---|---|---|
| D. lourinhanensis[27] | Praia da Amoreira-Porta Novo Member[27]
Praia Azul Member[23] |
One specimen. Vertebrae; potentially other parts of the body.[27] | A diplodocid. Tschopp et al. (2015) sunk the genus into Supersaurus.[27] Found at the top of the Porto Novo Member.[16] | ||
|
Diplodocidae indet. |
Intermediate |
Praia da Amoreira-Porto Novo Member[16] |
Variety of skeletal remains |
Remains of various indeterminate diplodocid specimens. Some are regarded as distinct taxa from Dinheirosaurus.[16] | |
|
L. alenquerensis[30] |
Praia Azul Member
Praia de Armoreia-Porto Novo Member[23] |
A partial postcranial skeleton. | Possibly a camarasaurid macronarian.[30] Possible specimens include SHN 002 from the Praia de Armoreia-Porto Novo Member.[16] | ||
| Praia Azul Member
Praia de Armoreia-Porto Novo Member[23] |
Fragmentary material.[31] |
A large brachiosaurid; a close relative of Brachiosaurus proper.[31] | |||
| Oceanotitan | O. dantasi[33] | Praia da Amoreira-Porta Novo Member | scapula, almost all of the pelvis, a complete leg sans the toes, and nine caudals. | A titanosauriform | |
| Zby[26] | Z. atlanticus[26] | Amoreira-Porto Novo Member[26] | Holotype: Tooth, cervical neutral arch, forelimb, various other fragments.[26] | A turiasaur.[26] Found at the top of the Porto Novo Member.[26] | |
| Flagellicaudata indet. | Indeterminate | Praia Azul Member[34] | Teeth; ML 2784 | Teeth from an indeterminate flagellicaudatan, possibly a diplodocid. The tooth from the Praia Azul Member has a dental morphology similar to that reported from juvenile diplodocines.[34][35] | |
|
Sauropoda indet. |
Indeterminate |
Praia da Amoreira-Porta Novo Member[36] |
Footprints |
Large footprints, possibly from a brachiosaurid or diplodocid | |
| Turiasauria indet. | Indeterminate | Praia Azul Member [16]
Praia da Amoreira-Porto Novo Member[34] |
Teeth | Teeth referred to indeterminate turiasaurs. Possibly from Zby. | |
Theropods
| Genus | Species | Member | Material | Notes | Images |
|---|---|---|---|---|---|
| Abelisauridae indet.[37] | Intermediate[37] | Praia da Amoreira-Porto Novo Member[4] | Teeth; ML 966, Ml 327.[37] | Potentially diagnostic abelisaur teeth[37] but these may represent allosauroid teeth instead.[38] | |
|
A. europaeus[39] |
Praia Azul Member[4]
|
Two specimens, covering much of the body.[42] |
Only European species of Allosaurus. | ||
|
A. fragilis[40] |
Praia Azul Member[4] |
Two specimens, covering much of the body.[42] |
Now thought to represent a specimen of A. europaeus.[39] | ||
|
Potentially a synonym of the type species, C. nasicornis. Sometimes referred to as C. sp., giving indication of possible distinctiveness or of being intermediate.[26] Remains also known from the Praia Azul Member. Remains come from Porto das Barcas, considered part of the Sobral Fm/Praia Azul Member.[16][47][4] | |||||
| Dendroolithidae[2] | Indeterminant | Fragments of multiple eggs in a clutch, with associated embryonic remains.[2] | Probably eggs of Torvosaurus.[2] | ||
| Lusovenator[48] | L. santosi[48] | Two partial postcranial skeletons.[48] | Earliest known Carcharodontosaurian from Laurasia.[48] | ||
| Praia Azul Member[49] |
Three individuals, one largely complete; over 100 eggs with significant amount of skeletal material.[49] |
Has come out in various places in the tree, erroneously said to be a megalosaur,[39] mostly accepted to be a carnosaur, probably allosauroid, or basal coelurosaur. Currently unstable on the tree.[49] | |||
|
M. insignis[37] |
Teeth.[37] |
Invalid. Teeth belong to various other theropod taxa.[37] | |||
|
M. pombali[37] |
Teeth.[37] |
Invalid. Teeth belong to various other theropod taxa[37] | |||
|
M. sp.[37] |
Tooth fragment.[37] |
Invalid; Dubious.[37] | |||
|
R. aff. gilmorei[37] |
Tooth; ML 939[37] |
Only definite record of this taxon is from the Late Cretaceous of North America, despite erroneous and referrals from other sites in Portugal. Probably a close relative of Richardoestesia and not an actual representation of the taxon.[37] | |||
|
T. gurneyi[50] |
Maxilla, Teeth, Femur; Egg clutch and embryos.[2][39][50][53] |
Largest known European theropod. Previous known as Portugal populations of the type species, or as T. sp., before description in early 2014.[50] | |||
|
T. tanneri[50] |
Now described as a distinct species of Torvosaurus, T. gurneyi. Sometimes referred to as T. sp. in the past.[50] | ||||
| Dromaeosauridae? indet. | Indeterminate | Praia Azul Member[54] | Teeth | Teeth pertaining to a possible dromaeosaur. | |
| Elaphrosaurinae Indet. | Indeterminate | Praia da Armoreia de-Porto Novo Member | ML 2050; skeletal remains | An indeterminate elaphrosaurine closely related to Elaphrosaurus[55] | |
Pterosaurs
| Genus | Species | Member | Material | Notes | Images |
|---|---|---|---|---|---|
| Dsungaripteroidea indet.[56] | Indeterminate | Praia da Amoreira-Porto Novo Member | Proximal right femur | A very large femur of a basal dsungaripteroid | |
| Rhamphorhynchidae[57] | Indeterminate | Tooth | |||
| Lusognathus | L. almadrava | Praia Azul Member[58] | Skull and cervical vertebrae | A Ctenochasmatid pterosaur | |
| Pteraichnus[59] | Partial tracks | ||||
Mammaliaformes
Docodonta
| Genus | Species | Member | Material | Notes |
|---|---|---|---|---|
|
H. expectatus |
Partial skeleton and isolated bones |
Semi-aquatic docodont | ||
Cladotheria
| Genus | Species | Member | Material | Notes |
|---|---|---|---|---|
|
D. acutum |
Upper jaw. |
Paurodontidae; herbivore. | ||
|
Guimarotodus |
G. inflatus |
Right mandible. |
Dryolestidae; insectivore or omnivore. | |
|
Krebsotherium |
K. lusitanicum |
Left mandible. |
Dryolestidae; insectivore or omnivore. | |
|
N. drescherae |
Right lower molar. |
Amphitheriidae; small omnivore or insectivore. | ||
Multituberculata
| Genus | Species | Member | Material | Notes |
|---|---|---|---|---|
| Kuehneodon | K. hahni | A member of the family Paulchoffatiidae |
Amphibians
| Genus | Species | Member | Material | Notes |
|---|---|---|---|---|
| Celtedens | Indeterminate | Porto Novo/Praia da Amoreira, Praia Azul | Frontal bones,[60] along with other parts of the skull and limbs[57] | An albanerpetontid. |
| Nabia[61] | civiscientrix | Porto Novo/Praia da Amoreira, Praia Azul. | 468 bones including skull, vertebral, and limb elements. | An albanerpetontid. |
| Urodela[57] | Indeterminate | Atlas vertebra | A salamander, suggested to belong to Scapherpetontidae. | |
| "Discoglossidae"[57] | Indeterminate | Partial left humerus | A primitive frog |
Squamates
| Genus | Species | Member | Material | Notes |
|---|---|---|---|---|
| Paramacellodidae[57] | Indeterminate | Frontal and dentary bones | Scincomorph lizard |
Crocodyliformes
| Genus | Species | Member | Material | Notes | Images |
|---|---|---|---|---|---|
| Machimosaurus | M. hugii | Praia Azul Member | Isolated teeth[62] | A large thalattosuchian crocodylomorph. Widespread, only found in the Praia Azul Member due to the area's marine deposits. |
|
| Ophiussasuchus | O. paimogonectes | Praia Azul Member | Partial skull | Goniopholidid | |
| Goniopholididae | Indeterminate | Teeth[63] and partial skeleton.[64] | An aquatic neosuchian | ||
| Bernissartiidae | Tooth[63] | ||||
| Lusitanisuchus | Teeth, and partial skull and jaw fragments[63] | A mesoeucrocodylian of uncertain placement | |||
| Atoposauridae | Partial skull table and braincase[65] Teeth[63] |
||||
| Mesoeucrocodylia | Teeth[63] | Distinct from Lusitanisuchus |
Fish
| Genus | Species | Member | Material | Notes |
|---|---|---|---|---|
| Hybodus[66] | H. cf. reticulatus | Teeth | A hybodontid shark | |
| Pycnodontiformes[57] | Indeterminate | |||
| Lepidotes sensu lato[57] | A ginglymodian | |||
| Caturus[57] | An amiiform |
Flora
| Genus | Species | Member | Material | Notes | Images |
|---|---|---|---|---|---|
| Classopollis[4] | Pollen of Cheirolepidiaceae conifers | ||||
| Cupressinocladus[4] | Conifer leaves | ||||
| Protocupressinoxylon[67] | Conifer wood | ||||
| Prototaxoxylon[67] | |||||
| Pterophyllum | P. mondeguensis[68] | Bennettitales leaf | |||
| Otozamites[4] | Bennettitales leaf | ||||
Correlation
| Ma | Age | Paleomap \ Basins | Cantabrian | Olanyà | Cameros | Maestrazgo | Oliete | Galve | Morella | South Iberian | Pre-betic | Lusitanian | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 100 | Cenomanian | La Cabana | Sopeira | Utrillas | Mosquerela | Caranguejeira | ||||||||
| Altamira | Utrillas | |||||||||||||
| Eguino | ||||||||||||||
| 125 | Albian | Ullaga - Balmaseda | Lluçà | Traiguera | ||||||||||
| Monte Grande | Escucha | Escucha | Jijona | |||||||||||
| Itxina - Miono | ||||||||||||||
| Aptian | Valmaseda - Tellamendi | Ol Gp. - Castrillo | Benassal | Benassal | Olhos | |||||||||
| Font | En Gp. - Leza | Morella/Oliete | Oliete | Villaroya | Morella | Capas Rojas | Almargem | |||||||
| Patrocinio - Ernaga | Senyús | En Gp. - Jubela | Forcall | Villaroya | Upper Bedoulian | Figueira | ||||||||
| Barremian | Vega de Pas | Cabó | Abejar | Xert | Alacón | Xert | Huérguina | Assises | ||||||
| Prada | Artoles | Collado | Moutonianum | Papo Seco | ||||||||||
| Rúbies | Tera Gp. - Golmayo | Alacón/Blesa | Blesa | Camarillas | Mirambel | |||||||||
| 150 | Hauterivian | Ur Gp. - Pinilla | Llacova | Castellar | Tera Gp. - Pinilla | Villares | Porto da Calada | |||||||
| hiatus | ||||||||||||||
| Huerva | Gaita | |||||||||||||
| Valanginian | Villaro | Ur Gp. - Larriba | Ped Gp. - Hortigüela | |||||||||||
| Ped Gp. - Hortigüela | Ped Gp. - Piedrahita | |||||||||||||
| Peñacoba | Galve | Miravetes | ||||||||||||
| Berriasian | Cab Gp. - Arcera | Valdeprado | hiatus | Alfambra | ||||||||||
| TdL Gp. - Rupelo | Arzobispo | hiatus | Tollo | |||||||||||
| On Gp. - Huérteles Sierra Matute | ||||||||||||||
| Tithonian | Lastres | Tera Gp. - Magaña | Higuereles | Tera Gp. - Magaña | Lourinhã | |||||||||
| Arzobispo | ||||||||||||||
| Ágreda | ||||||||||||||
| Legend | Major fossiliferous, oofossiliferous, ichnofossiliferous, coproliferous, minor formation | |||||||||||||
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